Air conditioning system for motor vehicles

ABSTRACT

An air conditioning system for motor vehicles includes an air conditioner case having a drainage port, an evaporator installed within the air conditioner case, a drainage hose configured to discharge condensate water generated in the evaporator to the outside of a vehicle room, the drainage hose connected to the drainage port and drawn out to the outside of the vehicle room through a dashboard, and a connector means configured to rotatably connect the drainage hose to the drainage port of the air conditioner case so as to permit rotation of the drainage hose with respect to the drainage port when the drainage hose is twisted in an assembling process of the drainage hose.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This patent application is a U.S. National Phase patent application ofPCT/KR2014/011797 filed Dec. 4, 2014 which claims priority to KR10-2014-0006596 filed Jan. 20, 2014, KR 10-2014-0006604 filed on Jan.20, 2014, and KR 10-2014-0006605 filed Jan. 20, 2014, the disclosure ofeach of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates to an air conditioning system for motorvehicles. More particularly, the present invention pertains to an airconditioning system for motor vehicles which is capable of preventing atwisting phenomenon of a condensate water drainage hose in the course ofassembling the condensate water drainage hose.

BACKGROUND ART

A motor vehicle is provided with an air conditioning system for coolingor heating the interior of a vehicle room. As shown in FIG. 1, an airconditioning system includes an air conditioner case 10 and anevaporator 12 installed in the air conditioner case 10. The evaporator12 is installed in an internal passage 10 a of the air conditioner case10 and is configured to cool an air blown along the internal passage 10a. This enables a cooled air to be introduced into a vehicle room.

The air conditioning system further includes a drainage device 20configured to discharge condensate water generated on the surface of theevaporator 12. The drainage device 20 includes a hopper-type bottomsurface 22 of the air conditioner case 10 configured to receive andcollect condensate water falling from the evaporator 12, a drainage port24 configured to drain the collected condensate water falling on thebottom surface 22 to the outside, and a drainage hose 26 configured toguide and discharge the condensate water drained from the drainage port24 to the outside of the vehicle room.

The drainage hose 26 extends to the outside of the vehicle room througha through-hole 32 of a dashboard 30. The drainage hose 26 serves todischarge the condensate water drained from the drainage port 24 to theoutside of the vehicle room.

Typically, when assembling the drainage hose 26, the base end portion 26a of the drainage hose 26 is fitted to the drainage port 24 of the airconditioner case 10. The distal end portion 26 b of the drainage hose 26is inserted into the through-hole 32 of the dashboard 30 and is drawn tothe outside of the dashboard 30. Finally, the distal end portion 26 b ofthe drainage hose 26 is pulled outside the dashboard 30.

In the course of pulling and drawing out the distal end portion 26 b ofthe drainage hose 26 outside the dashboard 30, the drainage hose 26 maybe distorted and twisted. This poses a problem in that the drainage hose26 is clogged due to the twisting phenomenon thereof.

Particularly, the twisting phenomenon of the drainage hose 26 occursmostly inside the dashboard 30. In this case, a worker who conducts adrawing work outside the dashboard 30 cannot recognize occurrence of thetwisting phenomenon of the drainage hose 26. Thus, the drainage hose 26may be assembled in a twisted state. This leads to a problem in thatpoor assembly of the drainage hose 26 occurs.

Consequently, there is a possibility that the inner diameter of thedrainage hose 26 is reduced or the drainage hose 26 is clogged. As aresult, the condensate water is not smoothly drained and the leakage ofcondensate water may be generated.

SUMMARY OF THE INVENTION Problems to be Solved

In view of the aforementioned problems inherent in the related art, itis an object of the present invention to provide an air conditioningsystem for motor vehicles which is capable of preventing a twistingphenomenon of a drainage hose in the course of assembling the drainagehose.

Another object of the present invention is to provide an airconditioning system for motor vehicles which is configured to prevent atwisting phenomenon of a drainage hose in the course of assembling thedrainage hose and which is capable of reliably preventing a cloggingphenomenon of the drainage hose attributable to the twist of thedrainage hose and the resultant leakage of condensate water.

Technical Solutions

In order to achieve the above objects, there is provided an airconditioning system for motor vehicles, including: an air conditionercase having a drainage port; an evaporator installed within the airconditioner case; a drainage hose configured to discharge condensatewater generated in the evaporator to the outside of a vehicle room, thedrainage hose connected to the drainage port and drawn out to theoutside of the vehicle room through a dashboard, and a connector meansconfigured to rotatably connect the drainage hose to the drainage portof the air conditioner case so as to permit rotation of the drainagehose with respect to the drainage port when the drainage hose is twistedin an assembling process of the drainage hose.

In the air conditioning system, the connector means may include: arotation guiding projection formed on an outer circumferential surfaceof the drainage port; and a connector fixedly secured to the drainagehose and fitted to the outer circumferential surface of the drainageport so as to rotate along the rotation guiding projection.

In air conditioning system, the rotation guiding projection may protrudefrom the outer circumferential surface of the drainage port, theconnector may include a port connection portion rotatably fitted to theouter circumferential surface of the drainage port, and the portconnection portion may include a rotation guiding rail formed on aninner circumferential surface of the port connection portion andconfigured to engage with the rotation guiding projection of thedrainage port so that the rotation guiding rail slides along acircumferential direction.

In the air conditioning system, the connector may further include anopening portion formed by cutting out a portion of the port connectionportion in the vicinity of the rotation guiding rail, and the openingportion may be configured to permit elastic deformation of a portion ofthe port connection portion having the rotation guiding rail so that therotation guiding rail is elastically deformed radially outward when theport connection portion of the connector is fitted to the outercircumferential surface of the drainage port.

The air conditioning system may further comprising: a sealing meansconfigured to water-tightly seal a gap between the drainage port and theconnector.

Advantageous Effects

According to the present air conditioning system for motor vehicles, thedrainage hose is rotatably assembled with the air conditioner case.Thus, there is provided an effect of being able to actively cope with asituation where the drainage hose is twistingly rotated in the processof drawing out and assembling the drainage hose outside the vehicleroom.

Furthermore, since it is possible to actively cope with the situationwhere the drainage hose is twistingly rotated in the process of drawingout and assembling the drainage hose outside the vehicle room, there isprovided an effect of being able to reliably prevent a twistingphenomenon of the drainage hose which may otherwise be generated whenthe drainage hose is twistingly rotated in the process of assembling thedrainage hose.

Furthermore, since it is possible to prevent the twisting phenomenon ofthe drainage hose in the process of assembling the drainage hose, thereis provided an effect of being able to reliably prevent a cloggingphenomenon of the drainage hose attributable to the twist of thedrainage hose and the resultant leakage of condensate water.

In addition, the drainage hose is rotatably assembled with the drainageport of the air conditioner case through the connector. The connectionportion between the drainage port of the air conditioner case and theconnector, from which water may be leaked, is water-tightly sealed bythe seal means. Thus, there is provided an effect of being able toreliably prevent leakage of water from between the drainage port of theair conditioner case and the connector.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view showing a conventional air conditioningsystem for motor vehicles.

FIG. 2 is a sectional view illustrating an air conditioning system formotor vehicles according to a first embodiment of the present invention,in which view major characterizing parts are illustrated in an explodedstate.

FIG. 3 is a perspective view illustrating the air conditioning systemfor motor vehicles according to the first embodiment of the presentinvention, in which view major characterizing parts are illustrated inan exploded state.

FIG. 4 is an enlarged sectional view illustrating a state in which adrainage port, a connector and a drainage hose, as major characterizingparts of the first embodiment, are exploded.

FIG. 5 is a sectional view illustrating a state in which the drainageport, the connector and the drainage hose illustrated in FIG. 2 areassembled together.

FIG. 6 is a perspective view illustrating a state in which the drainageport, the connector and the drainage hose illustrated in FIG. 2 areassembled together.

FIG. 7 is an enlarged sectional view illustrating a state in which thedrainage port, the connector and the drainage hose, as majorcharacterizing parts of the first embodiment, are assembled together.

FIG. 8 is a sectional view illustrating an air conditioning system formotor vehicles according to a second embodiment of the presentinvention, in which view a drainage port, a connector, a drainage hoseand a sealing means of the drainage port and the connector, as majorcharacterizing parts of the second embodiment, are illustrated in anexploded state.

FIG. 9 is a sectional view illustrating a state in which the drainageport, the connector, the drainage hose and the sealing means illustratedin FIG. 8 are assembled together.

FIG. 10 is a sectional view illustrating a first modification of thesealing means of the air conditioning system according to the secondembodiment, in which view the drainage port, the connector, the drainagehose and the sealing means are illustrated in an exploded state.

FIG. 11 is a sectional view illustrating a state in which the drainageport, the connector, the drainage hose and the sealing means illustratedin FIG. 10 are assembled together.

FIG. 12 is a sectional view illustrating a second modification of thesealing means of the air conditioning system according to the secondembodiment, in which view a drainage port, a connector, a drainage hoseand a sealing means are illustrated in an exploded state.

FIG. 13 is a sectional view illustrating the second modification of thesealing means of the air conditioning system according to the secondembodiment, in which view the drainage port, the connector, the drainagehose and the sealing means are illustrated in an exploded state.

FIG. 14 is a sectional view illustrating a state in which the drainageport, the connector, the drainage hose and the sealing means illustratedin FIG. 13 are assembled together.

FIG. 15 is a sectional view illustrating a third modification of thesealing means of the air conditioning system according to the secondembodiment.

MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of an air conditioning system for motor vehiclesaccording to the present invention will now be described in detail withreference to the accompanying drawings. Components similar to those ofthe related art described earlier will be designated by like referencesymbols.

First Embodiment

Prior to describing features of an air conditioning system for motorvehicles according to the present invention, an air conditioning systemfor motor vehicles will be briefly described with reference to FIG. 2.

The air conditioning system includes an air conditioner case 10 and anevaporator 12 installed in the air conditioner case 10. The evaporator12 is installed in an internal passage 10 a of the air conditioner case10 and is configured to cool an air blown along the internal passage 10a.

The air conditioning system further includes a drainage device 20configured to discharge condensate water generated on the surface of theevaporator 12. The drainage device 20 includes a hopper-type bottomsurface 22 of the air conditioner case 10 configured to receive andcollect condensate water falling from the evaporator 12, a drainage port24 configured to drain the collected condensate water falling on thebottom surface 22 to the outside, and a drainage hose 26 configured toguide and discharge the condensate water drained from the drainage port24 to the outside of the vehicle room.

The drainage hose 26 extends to the outside of the vehicle room througha through-hole 32 of a dashboard 30. The drainage hose 26 serves todischarge the condensate water drained from the drainage port 24 to theoutside of the vehicle room.

Typically, when assembling the drainage hose 26, the base end portion 26a of the drainage hose 26 is fitted to the drainage port 24 of the airconditioner case 10. The distal end portion 26 b of the drainage hose 26is inserted into the through-hole 32 of the dashboard 30 and is drawn tothe outside of the dashboard 30. Finally, the distal end portion 26 b ofthe drainage hose 26 is pulled outside the dashboard 30.

Next, features of the air conditioning system for motor vehiclesaccording to the present invention will be described in detail withreference to FIGS. 2 to 7.

The air conditioning system according to the present invention includesa drainage port 24 of the drainage device 20. A rotation guidingprojection 40 is formed on the outer circumferential surface of thedrainage port 24. The rotation guiding projection 40 is formed toprotrude from the outer circumferential surface of the drainage port 24.Although a plurality of rotation guiding projections may be formed onthe outer circumferential surface of the drainage port 24, it ispreferred that one rotation guiding projection is formed on the outercircumferential surface of the drainage port 24.

As illustrated in FIG. 4, the rotation guiding projection 40 protrudesfrom the outer circumferential surface of the drainage port 24 so thatthe protrusion height A1 thereof becomes equal to 1.5/10 of the outerdiameter A2 of the drainage port 24.

Referring again to FIGS. 2 to 7, the air conditioning system accordingto the present invention includes a connector 50 configured to rotatablyconnect the drainage hose 26 to the drainage port 24. The connector 50is a tubular body having a bore 50 a. The connector 50 includes a hoseconnection portion 52 formed at one end thereof and a port connectionportion 54 formed at the other end thereof.

The hose connection portion 52 is fitted to a bore 26 c of the drainagehose 26. A plurality of coupling projections 52 a is formed on the outercircumferential surface of the hose connection portion 52. The couplingprojections 52 a protrude radially outward from the outercircumferential surface of the hose connection portion 52. The couplingprojections 52 a are formed at regular intervals along thecircumferential direction of the hose connection portion 52.

When the hose connection portion 52 of the connector 50 is fitted to thebore 26 c of the drainage hose 26, the coupling projections 52 a engagewith the inner circumferential surface of the drainage hose 26, therebyincreasing the coupling force between the drainage hose 26 and the hoseconnection portion 52. Specifically, the coupling projections 52 a cutinto and engage with the inner circumferential surface of the drainagehose 26 in the process of fitting the hose connection portion 52 intothe bore 26 c of the drainage hose 26. Thus, the coupling projections 52a enhance the coupling force between the drainage hose 26 and the hoseconnection portion 52. This prevents separation of the hose connectionportion 52 of the connector 50 and the drainage hose 26.

As illustrated in FIGS. 4 and 7, it is preferred that the couplingprojections 52 a protruding from the outer circumferential surface ofthe hose connection portion 52 have a triangular cross section. Morepreferably, the coupling projections 52 a may protrude from the outercircumferential surface of the hose connection portion 52 in aright-triangular cross section.

Each of the coupling projections 52 a having a right-triangular crosssection includes a slant side portion 52 b and a perpendicular sideportion 52 c. The slant side portion 52 b oriented in a couplingdirection in which the hose connection portion 52 is coupled to thedrainage hose 26. The perpendicular side portion 52 c is oriented in adirection opposite to the coupling direction.

By employing this configuration, when the connector 50 is assembled withthe drainage hose 26, the coupling projections 52 a smoothly slide alongthe inner circumferential surface of the drainage hose 26, therebyassuring smooth assembly of the connector 50 and the drainage hose 26.After the connector 50 is assembled with the drainage hose 26, thecoupling projections 52 a make contact with the inner circumferentialsurface of the drainage hose 26 with a large friction force, therebyincreasing the coupling force between the connector 50 and the drainagehose 26.

In addition, it is preferred that each of the coupling projections 52 aprotruding from the outer circumferential surface of the hose connectionportion 52 has a sharp end portion. It is also preferred that theprotruding height A3 of each of the coupling projections 52 a issubstantially equal to ⅓ of the wall thickness A4 of the drainage hose26.

Furthermore, it is preferred that each of the coupling projections 52 aprotruding from the outer circumferential surface of the hose connectionportion 52 is spaced apart by a distance A5 of at least 5 mm from theterminal end of the hose connection portion 52. More preferably, each ofthe coupling projections 52 a may be spaced apart by a distance A5 of atleast 5 mm from the terminal end of a contact section 22 d of the hoseconnection portion 52 making contact with the drainage hose 26.

The coupling projections 52 a are formed on the outer circumferentialsurface of the hose connection portion 52 at regular intervals along thecircumferential direction and are arranged in a zigzag pattern along thecircumferential direction.

By employing this configuration, it is possible to widen the arrangementarea of the coupling projections 52 a. This makes it possible to widenthe friction contact area between the coupling projections 52 a and thedrainage hose 26 and to increase the coupling force between the couplingprojections 52 a and the drainage hose 26.

The reason for arranging the coupling projections 52 a in the zigzagpattern is to prevent a portion of the drainage hose 26 from excessivelyexpanding radially outward in the process of assembling the hoseconnection portion 52 and the drainage hose 26.

In a case where the coupling projections 52 a are arranged in a linealong the circumferential direction of the hose connection portion 52, aportion of the drainage hose 26 may be excessively expanded radiallyoutward in the process of assembling the hose connection portion 52 andthe drainage hose 26. This may make it difficult to assemble the hoseconnection portion 52 and the drainage hose 26.

If the coupling projections 52 a are arranged in the zigzag pattern asin the present invention, the drainage hose 26 is sequentially expandedin the process of assembling the hose connection portion 52 and thedrainage hose 26. Thus, the expansion amount of the drainage hose 26 isreduced. This makes it easy to assemble the hose connection portion 52and the drainage hose 26. As a result, the ease of assembly of thedrainage hose 26 is remarkably improved.

Referring again to FIGS. 2 to 7, the port connection portion 54 of theconnector 50 is rotatably fitted to the outer circumferential surface ofthe drainage port 24. The port connection portion 54 includes a rotationguiding rail 60 formed on the inner circumferential surface thereof.

The rotation guiding rail 60 is one kind of protrusion rib protrudingradially inward from the inner circumferential surface of the portconnection portion 54 and extending along the circumferential direction.The rotation guiding rail 60 has a substantially triangular crosssection.

When the port connection portion 54 of the connector 50 is fitted to thedrainage port 24, the rotation guiding rail 60 slidably engages with therotation guiding projection 40 of the drainage port 24. The rotationguiding rail 60 slidably engaging with the rotation guiding projection40 connects the connector 50 to the drainage port 24 so that theconnector 50 can rotate with reference to the drainage port 24.

Accordingly, the connector 50 and the drainage hose 26 coupled with theconnector 50 can rotate with reference to the drainage port 24. Thismakes it possible to cope with the twist of the drainage hose 26 whichmay be twistingly rotated in the process of assembling the drainage hose26.

In particular, it is possible to actively cope with the twist of thedrainage hose 26 which may be twisted in the process of drawing out thedrainage hose 26 outside the vehicle room. As a result, it is possibleto reliably prevent a twisting phenomenon of the drainage hose 26. Thismakes it possible to reliably prevent a clogging phenomenon of thedrainage hose 26 attributable to the twist of the drainage hose 26 and aleakage phenomenon of condensate water attributable to the cloggingphenomenon of the drainage hose 26.

As illustrated in FIG. 4, the rotation guiding rail 60 protrudesradially inward from the inner circumferential surface of the portconnection portion 54 so that the protruding height A6 thereof is largerthan the protruding height A1 of the rotation guiding projection 40 withrespect to the outer circumferential surface of the drainage port 24.

By employing this configuration, when the port connection portion 54 ofthe connector 50 is fitted to the outer circumferential surface of thedrainage port 24 as illustrated in FIG. 7, a gap C is formed between theinner circumferential surface of the port connection portion 54 and therotation guiding projection 40 of the drainage port 24 due to thedifference between the protruding heights A1 and A6 of the rotationguiding rail 60 and the rotation guiding projection 40. This makes itpossible to prevent direct friction contact between the rotation guidingprojection 40 of the drainage port 24 and the inner circumferentialsurface of the port connection portion 54.

The reason for preventing the direct friction contact between therotation guiding projection 40 of the drainage port 24 and the innercircumferential surface of the port connection portion 54 is to minimizethe friction contact force between the drainage port 24 and theconnector 50, thereby allowing smooth rotation of the connector 50.

It is preferred that the gap C between the rotation guiding projection40 of the drainage port 24 and the inner circumferential surface of theport connection portion 54 of the connector 50 is equal to 1/10 of theouter diameter A2 of the drainage port 24.

In the present embodiment, the rotation guiding projection 40 is formedin the drainage port 24. The rotation guiding rail 60 is formed in theconnector 50. The relative rotational movement between the drainage port24 and the connector 50 is guided using the rotation guiding projection40 and the rotation guiding rail 60. Alternatively, if necessary, therotation guiding rail 60 may be formed in the drainage port 24. Therotation guiding projection 40 may be formed in the connector 50. Therelative rotational movement between the drainage port 24 and theconnector 50 can be guided using the rotation guiding rail 60 and therotation guiding projection 40 thus formed.

It is preferred that the rotation guiding projection 40 is formed in thedrainage port 24 and the rotation guiding rail 60 is formed in theconnector 50 so that the relative rotational movement between thedrainage port 24 and the connector 50 is guided by the rotation guidingprojection 40 and the rotation guiding rail 60. The reason is that if herotation guiding projection 40 is formed in the connector 50 as arotating body, the rotation guiding projection 40 may be easily damagedor broken during the rotation of the connector 50.

By forming the rotation guiding projection 40 in the drainage port 24 asa fixed body, it is possible to suppress damage or breakage of therotation guiding projection 40, thereby improving the durabilitythereof.

In the present embodiment, there has been described an example in whichone rotation guiding projection 40 is formed in the drainage port 24.However, if necessary, a plurality of rotation guiding projections maybe formed in the drainage port 24.

It is preferred that one rotation guiding projection 40 is formed in thedrainage port 24. The reason is that as the number of rotation guidingprojections increases, the contact area between the drainage port 24 andthe connector 50 grows larger, eventually making it difficult for theconnector 50 to rotate.

By forming one rotation guiding projection 40 in the drainage port 24,it is possible to enable smooth rotation of the connector 50 while notreducing the coupling force between the drainage port 24 and theconnector 50.

Referring again to FIGS. 2 to 7, the air conditioning system of thepresent invention includes opening portions 70 formed in the portconnection portion 54 of the connector 50. The opening portions 70 areformed to extend through the thickness of the connector 50 from theouter circumferential surface of the port connection portion 54. Theopening portions 70 are formed in a pair along the circumferentialdirection of the port connection portion 54.

The opening portions 70 are symmetrically formed in the port connectionportion 54 so as to face each other. The opening portions 70 are formedin the vicinity of the rotation guiding rail 60 of the port connectionportion 54.

Since the opening portions 70 configured as above have a mutually-facingsymmetrical structure, it is possible to easily secure the orientationof a mold when injection-molding the connector 50. Specifically, wheninjection-molding the internal parts of the port connection portion 54,for example, the rotation guiding rail 60, it is possible to easilysecure the orientation of a mold for molding the rotation guiding rail60. Accordingly, it is possible to facilitate the injection-molding ofthe connector 50, consequently improving the productivity of theconnector 50.

In addition, since the opening portions 70 are formed in the vicinity ofthe rotation guiding rail 60, the region of the port connection portion54 where the rotation guiding rail 60 is formed can be elasticallydeformed.

Accordingly, when the port connection portion 54 of the connector 50 isfitted to the outer circumferential surface of the drainage port 24, theport connection portion 54 is elastically deformed so that the portconnection portion 54 of the connector 50 can be easily fitted to theouter circumferential surface of the drainage port 24.

In particular, when the rotation guiding rail 60 of the connector 50 isfitted to the drainage port 24 while making friction contact with theouter surface of the rotation guiding projection 40, the port connectionportion 54 can be deformed radially outward in the rotation guiding rail60. This makes it possible to improve the ease of assembly of theconnector 50 with respect to the rotation guiding projection 40 of thedrainage port 24. As a result, it is possible to improve the ease ofassembly of the connector 50.

Referring again to FIGS. 2 to 7, the air conditioning system of thepresent invention includes a stopper 80 formed in the drainage port 24.The stopper 80 is formed on the outer circumferential surface of thedrainage port 24. As illustrated in FIGS. 5 and 7, the stopper 80 isconfigured such that the end portion of the connector 50 fitted to thedrainage port 24 collides and interferes with the stopper 80.Specifically, the stopper 80 is disposed such that the end portion ofthe connector 50 fitted to the rotation guiding projection 40 of thedrainage port 24 collides and interferes with the stopper 80.

When the connector 50 temporarily fitted to drainage port 24 is movedtoward the stopper 80 beyond a right assembly position in an insertiondirection, the stopper 80 interferes with the connector 50, therebyrestraining the movement of the connector 50. Thus, the stopper 80prevents the connector 50 from being excessively fitted to the outercircumferential surface of the drainage port 24 when the connector 50 isassembled with the drainage port 24. This makes it possible to preventinaccurate assembly of the connector 50 and the resultant locking of theconnector 50. Thus, the stopper 80 assists in enabling smooth rotationof the connector 50.

Next, an operation example of the air conditioning system configured asabove will be described with reference to FIGS. 2 to 7.

First, as illustrated in FIG. 2, the connector 50 is assembled with thedrainage port 24 of the air conditioner case 10. In this case, the portconnection portion 54 of the connector 50 is fitted to the drainage port24 of the air conditioner case 10. Then, the rotation guiding rail 60 ofthe port connection portion 54 is slidably supported on the rotationguiding projection 40. The connector 50 thus assembled is rotatablyconnected to the drainage port 24 of the air conditioner case 10 so thatthe connector 50 can rotate around the drainage port 24.

After the assembly of the connector 50 with the drainage port 24 iscompleted, the drainage hose 26 is assembled with the connector 50. Inthis case, the base end portion 26 a of the drainage hose 26 is fittedto the hose connection portion 52 of the connector 50. In the process ofassembling the drainage hose 26 with the connector 50, the couplingprojections 52 a of the connector 50 cut into the inner circumferentialsurface of the drainage hose 26 and engage with the innercircumferential surface of the drainage hose 26. Thus, drainage hose 26and the hose connection portion 52 of the connector 50 are assembledwith a high coupling force.

After the assembly of the drainage hose 26 with the connector 50 iscompleted, as illustrated in FIG. 5, the terminal end portion of thedrainage hose 26 is inserted into the through-hole 32 of the dashboard30 and is drawn out to the outside of the vehicle room. Then, thedrainage hose 26 is pulled outward. Thus, the drainage hose 26 kept in aslackened state within the vehicle room is stretched to the outside ofthe vehicle room, whereby the drainage hose 26 tensely extends from theinside of the vehicle room to the outside thereof.

If the drainage hose 26 is twisted in the process of pulling thedrainage hose 26, the drainage hose 26 and the connector 50 rotate withrespect to the drainage port 24 of the air conditioner case 10, therebyactively untwisting the drainage hose 26. As a result, it is possible toreliably prevent a twisting phenomenon of the drainage hose 26.

According to the air conditioning system configured as above, thedrainage hose 26 is rotatably assembled with the air conditioner case10. Thus, it is possible to actively cope with a situation where thedrainage hose 26 is twistingly rotated in the process of drawing out andassembling the drainage hose 26 outside the vehicle room.

Furthermore, since it is possible to actively cope with the situationwhere the drainage hose is twistingly rotated in the process of drawingout and assembling the drainage hose outside the vehicle room, it ispossible to reliably prevent a twisting phenomenon of the drainage hose26 which may otherwise be generated when the drainage hose 26 istwistingly rotated in the process of assembling the drainage hose 26.

In addition, since it is possible to prevent the twisting phenomenon ofthe drainage hose 26 in the process of assembling the drainage hose 26,it is possible to reliably prevent a clogging phenomenon of the drainagehose 26 attributable to the twist of the drainage hose 26 and theresultant leakage of condensate water.

Second Embodiment

Next, an air conditioning system for motor vehicles according to asecond embodiment of the present invention will be described withreference to FIGS. 8 to 15.

Referring first to FIGS. 8 and 9, the air conditioning system of thesecond embodiment is identical in basic configuration with the airconditioning system of the first embodiment described above.

The air conditioning system of the second embodiment further includes asealing means configured to water-tightly seal a gap between thedrainage port 24 of the air conditioner case 10 and the connector 50fitted to the drainage port 24.

The sealing means includes a terminal end portion 90 of the hoseconnection portion 52 of the connector 50, which makes contact with theouter circumferential surface of the drainage port 24, and protrusionportions 92 formed on the outer circumferential surface of the drainageport 24 in a corresponding relationship with the terminal end portion 90of the hose connection portion 52.

The terminal end portion 90 of the hose connection portion 52 of theconnector 50 is configured to make contact with the outercircumferential surface of the drainage port 24 when fitting theconnector 50 to the outer circumferential surface of the drainage port24. The terminal end portion 90 makes contact with the outercircumferential surface of the drainage port 24 along thecircumferential direction.

The protrusion portions 92 protrude from the outer circumferentialsurface of the drainage port 24 in a corresponding relationship with theterminal end portion 90 of the connector 50. Specifically, theprotrusion portions 92 protrude in an annular shape along the outercircumferential surface of the drainage port 24 with which the terminalend portion 90 of the connector 50 makes contact.

The protrusion portions 92 make contact with the terminal end portion 90of the connector 50. Thus, the protrusion portions 92 eliminates aclearance which may otherwise exist between the outer circumferentialsurface of the drainage port 24 and the terminal end portion 90 of theconnector 50. Consequently, the protrusion portions 92 water-tightlyseal a gap between the outer circumferential surface of the drainageport 24 and the terminal end portion 90 of the connector 50, therebyenhancing the water-tightness between the drainage port 24 and theconnector 50. It is therefore possible to prevent condensate water frombeing leaked through between the drainage port 24 and the connector 50.

In this regard, the protrusion portions 92 protruding from the outercircumferential surface of the drainage port 24 are formed in a pair soas to interpose the terminal end portion 90 of the connector 50therebetween. Specifically, the protrusion portions 92 are formed on thedrainage port 24 at the inner side and outer side of the connector 50with respect to the terminal end portion 90 interposed between theprotrusion portions 92.

The protrusion portions 92 are arranged at the opposite sides of theterminal end portion 90 of the connector 50 so as to improve thewater-tightness between the outer circumferential surface of thedrainage port 24 and the terminal end portion 90 of the connector 50. Itis therefore possible to maximize an effect of preventing leakage ofcondensate water through between the drainage port 24 and the connector50.

It is preferred that the protrusion portions 92 of the drainage port 24are burrs formed on the outer circumferential surface of the drainageport 24 by the terminal end portion 90 of the hose connection portion 52when the terminal end portion 90 of the hose connection portion 52 ofthe connector 50 is pressed against the outer circumferential surface ofthe drainage port 24 and then the connector 50 is rotated.

When pressing the terminal end portion 90 of the connector 50 againstthe outer circumferential surface of the drainage port 24 in order toform the burrs as the protrusion portions 92, it may be possible tomanually press the terminal end portion 90 of the connector 50 againstthe outer circumferential surface of the drainage port 24.

However, it is preferred that the inner diameter L2 of the terminal endportion 90 of the connector 50 is set smaller than the outer diameter L1of the drainage port 24 so that the terminal end portion 90 of theconnector 50 is naturally pressed against the outer circumferentialsurface of the drainage port 24 in the process of fitting the connector50 to the outer circumferential surface of the drainage port 24.

The protrusion portions 92 of the drainage port 24 serve not only toimprove the water-tightness between the drainage port 24 and theconnector 50 but also to increase the coupling force of the drainageport 24 and the connector 50. Furthermore, the protrusion portions 92serve to guide the rotational movement of the connector 50.

The protrusion portions 92 serve to additionally guide the rotationalmovement of the connector 50 in cooperation with the rotation guidingprojection 40 and the rotation guiding rail 60 and serve to additionallycouple the connector 50 with the drainage port 24. Accordingly, evenwhen the rotation guiding projection 40 of the drainage port 24 and therotation guiding rail 60 of the connector 50 are separated from eachother, the protrusion portions 92 enable the connector 50 to smoothlyrotate with respect to the drainage port 24 while maintaining thecoupling of the drainage port 24 and the connector 50.

The protrusion portions 92 of the drainage port 24 may not be formed ofthe burrs mentioned above but may be formed of protrusion ribsintegrally formed with the drainage port 24 when injection-molding thedrainage port 24.

Similar to the burr-type protrusion portions 92 described above, therib-type protrusion portions 92 protrude from the outer circumferentialsurface of the drainage port 24 and make contact with the terminal endportion 90 of the connector 50, thereby improving the water-tightnessbetween the outer circumferential surface of the drainage port 24 andthe terminal end portion 90 of the connector 50. This makes it possibleto prevent leakage of condensate water through between the drainage port24 and the connector 50.

Referring next to FIGS. 10 and 11, there is illustrated a firstmodification of the sealing means for sealing a gap between the drainageport 24 and the connector 50.

The sealing means of the first modification includes a terminal endportion 90 of the hose connection portion 52 of the connector 50, whichis configured to water-tight contact with the outer circumferentialsurface of the drainage port 24. The terminal end portion 90 of the hoseconnection portion 52 of the connector 50 includes a freely-deformableflexural deformation portion 90 a having a thickness smaller than thethickness of the remaining portion of the terminal end portion 90.

The flexural deformation portion 90 a of the connector 50 is configuredto make water-tight contact with the outer circumferential surface ofthe drainage port 24 when fitting the connector 50 to the drainage port24. Specifically, the flexural deformation portion 90 a makeswater-tight contact with the outer circumferential surface of thedrainage port 24 along the circumferential direction. Thus, the flexuraldeformation portion 90 a water-tightly seals a gap between the outercircumferential surface of the drainage port 24 and the terminal endportion 90 of the connector 50. Accordingly, the flexural deformationportion 90 a enhances the air-tightness between the drainage port 24 andthe connector 50, thereby preventing leakage of condensate water throughbetween the drainage port 24 and the connector 50.

The flexural deformation portion 90 a should not apply an excessivepressing force to the outer circumferential surface of the drainage port24 when making water-tight contact with the outer circumferentialsurface of the drainage port 24. The reason is that if the flexuraldeformation portion 90 a applies an excessive pressing force to theouter circumferential surface of the drainage port 24, the rotation ofthe connector 50 may be hindered.

It is preferred that the inner diameter L3 of the flexural deformationportion 90 a is set smaller than the outer diameter L1 of the drainageport 24. The reason is that if the inner diameter L3 of the flexuraldeformation portion 90 a is smaller than the outer diameter L1 of thedrainage port 24, the flexural deformation portion 90 a of the connector50 can naturally make surface-to-surface contact with the outercircumferential surface of the drainage port 24 in the process offitting the connector 50 to the outer circumferential surface of thedrainage port 24.

Referring next to FIGS. 12 to 14, there is illustrated a secondmodification of the sealing means for sealing a gap between the drainageport 24 and the connector 50.

The sealing means of the second modification includes an O-ring 100installed between the outer circumferential surface of the drainage port24 and the inner circumferential surface of the connector 50.

As illustrated in FIG. 14, the O-ring 100 is fitted to the outercircumferential surface of the drainage port 24. One side surface of theO-ring 100 is supported by a shoulder surface 24 a formed on the outercircumferential surface of the drainage port 24 and the other sidesurface of the O-ring 100 elastically makes contact with a ring-holdingsurface 50 b of the connector 50.

The O-ring 100 configured as above water-tightly seals a gap between thedrainage port 24 and the connector 50, thereby enhancing thewater-tightness between the drainage port 24 and the connector 50. Thisprevents condensate water from being leaked through between the drainageport 24 and the connector 50 when the condensate water is dischargedfrom the drainage port 24 to the drainage hose 26.

The O-ring 100 is installed between the drainage port 24 and theconnector 50 in a position corresponding to the opening portions 70 ofthe connector 50. This enables a worker to visually recognize theinstallation state of the O-ring 100 through the opening portions 70 ofthe connector 50. With this configuration, it is possible to inspect theassembly state, the wear state and the damage or breakage of the O-ring100.

The shoulder surface 24 a of the drainage port 24, which supports oneside surface of the O-ring 100, is formed to make a right angle withrespect to the outer circumferential surface of the drainage port 24.The shoulder surface 24 a has a height B1 larger than the diameter B2 ofthe O-ring 100. For example, the height B1 of the shoulder surface 24 ais 1.5 times as large as the diameter B2 of the O-ring 100. The reasonfor employing this configuration is to prevent removal of the O-ring 100from the shoulder surface 24 a of the drainage port 24.

In addition, the ring-holding surface 50 b of the connector 50 makingcontact with the other side surface of the O-ring 100 is inclined withrespect to the outer circumferential surface of the drainage port 24.The ring-holding surface 50 b of the connector 50 inclined with respectto the outer circumferential surface of the drainage port 24 serves topress the O-ring 100 against the outer circumferential surface of thedrainage port 24, thereby enhancing the air-tightness between thedrainage port 24, the O-ring 100 and the connector 50.

It is preferred that the ring-holding surface 50 b of the connector 50corresponding to the shoulder surface 24 a of the drainage port 24 isinclined to make a predetermined angle α with respect to the shouldersurface 24 a of the drainage port 24. For example, the ring-holdingsurface 50 b of the connector 50 may be inclined to make an anglefalling within a range of about 30 to 45 degrees with respect to theshoulder surface 24 a of the drainage port 24.

The reason for employing this configuration is to assure that thepressing forces applied to one side surface and the other side surfaceof the O-ring 100 by the drainage port 24 and the connector 50 do notact against each other. In a case where the pressing forces applied toone side surface and the other side surface of the O-ring 100 by thedrainage port 24 and the connector 50 act against each other, therotation of the connector 50 may be hindered.

Since the ring-holding surface 50 b of the connector 50 is inclined withrespect to the outer circumferential surface of the drainage port 24,the ring-holding surface 50 b comes close to the shoulder surface 24 aof the drainage port 24 in the portion thereof corresponding to theradial outer portion of the O-ring 100. The gap B3 between the shouldersurface 24 a of the drainage port 24 and the portion of the ring-holdingsurface 50 b closest to the shoulder surface 24 a is set smaller thanthe diameter B2 of the O-ring 100. For example, the gap B3 may be set tobecome equal to ⅓ of the diameter B2 of the O-ring 100. The reason foremploying this configuration is to prevent the O-ring 100 from beingremoved from the gap between the ring-holding surface 50 b of theconnector 50 and the shoulder surface 24 a of the drainage port 24.

Referring next to FIG. 15, there is illustrated a third modification ofthe sealing means for sealing a gap between the drainage port 24 and theconnector 50.

The sealing means of the third modification differs from the sealingmeans of the second modification in terms of the structures of theconnector 50 and the drainage port 24 for installing the O-ring 100.

Specifically, in the sealing means of the second modification, theshoulder surface 24 a of the drainage port 24 is formed to make a rightangle with respect to the outer circumferential surface of the drainageport 24, and the ring-holding surface 50 b of the connector 50 isinclined.

In contrast, in the sealing means of the third modification, theshoulder surface 24 a of the drainage port 24 is inclined with respectto the outer circumferential surface of the drainage port 24, and thering-holding surface 50 b of the connector 50 makes a right angle withthe outer circumferential surface of the drainage port 24.

The shoulder surface 24 a of the drainage port 24 and the ring-holdingsurface 50 b of the connector 50 employed in the sealing means of thethird modification are opposite in shape and structure to those employedin the sealing means of the second modification. However, the functionand operation of the shoulder surface 24 a of the drainage port 24 andthe ring-holding surface 50 b of the connector 50 employed in thesealing means of the third modification are the same as those of thesecond embodiment.

According to the air conditioning system of the second embodimentconfigured as above, the drainage hose 26 is rotatably fitted to thedrainage port 24 through the use of the connector 50. The connectionregion of the drainage port 24 and the connector 50, from whichcondensate water may be leaked, is water-tightly sealed by the sealingmeans. It is therefore possible to reliably prevent leakage ofcondensate water through between the drainage port 24 and the connector50.

While some preferred embodiments of the present invention have beendescribed above, the present invention is not limited to theseembodiments. It is to be understood that various changes andmodifications may be made without departing from the scope of theinvention defined in the claims.

What is claimed is:
 1. An air conditioning system for motor vehicles,comprising: an air conditioner case having a drainage port; anevaporator installed within the air conditioner case; a drainage hoseconfigured to discharge condensate water generated in the evaporator toan outside of a vehicle room, the drainage hose connected to thedrainage port and drawn out to the outside of the vehicle room through adashboard; a connector means configured to rotatably connect thedrainage hose to the drainage port of the air conditioner case to permitrotation of the drainage hose with respect to the drainage port when thedrainage hose is twisted in an assembling process of the drainage hose,wherein the connector means includes a rotation guiding projectionformed on an outer circumferential surface of the drainage port and aconnector fixedly secured to the drainage hose and fitted to the outercircumferential surface of the drainage port to rotate along therotation guiding projection; and wherein a terminal end portion of theconnector extends along a circumferential direction and whereinprotrusion portions are continuously formed on the outer circumferentialsurface of the drainage port along the circumferential direction to makecontact with the terminal end portion of the connector and water-tightlyseal a gap between the terminal end portion of the connector and thedrainage port, and wherein the protrusion portions are formed on theouter circumferential surface of the drainage port at an inner side andan outer side of the connector with respect to the terminal end portioninterposed between the protrusion portions.
 2. The air conditioningsystem of claim 1, wherein the protrusion portions are burrs formed onthe outer circumferential surface of the drainage port by the terminalend portion of the connector when the terminal end portion of theconnector is pressed against the outer circumferential surface of thedrainage port and then the connector is rotated.
 3. The air conditioningsystem of claim 2, wherein an inner diameter of the terminal end portionof the connector is set smaller than an outer diameter of the drainageport so the terminal end portion of the connector is pressed against theouter circumferential surface of the drainage port in a process offitting the connector to the outer circumferential surface of thedrainage port.
 4. The air conditioning system of claim 1, wherein theprotrusion portions are ribs integrally formed with the drainage portwhen injection-molding the drainage port.
 5. An air conditioning systemfor motor vehicles, comprising: an air conditioner case having adrainage port; an evaporator installed within the air conditioner case;a drainage hose configured to discharge condensate water generated inthe evaporator to an outside of a vehicle room, the drainage hoseconnected to the drainage port and drawn out to the outside of thevehicle room through a dashboard; a connector means configured torotatably connect the drainage hose to the drainage port of the airconditioner case to permit rotation of the drainage hose with respect tothe drainage port when the drainage hose is twisted in an assemblingprocess of the drainage hose, wherein the connector means includes arotation guiding projection formed on an outer circumferential surfaceof the drainage port and a connector fixedly secured to the drainagehose and fitted to the outer circumferential surface of the drainageport to rotate along the rotation guiding projection; and wherein aterminal end portion of the connector is water-tightly pressed againstthe outer circumferential surface of the drainage port to water-tightlyseal a gap between the connector and the drainage port.
 6. The airconditioning system of claim 5, wherein the terminal end portion of theconnector includes a freely-deformable flexural deformation portionhaving a thickness smaller than a thickness of a remaining portion ofthe terminal end portion, the flexural deformation portion configured tomake water-tight contact with the outer circumferential surface of thedrainage port.
 7. The air conditioning system of claim 6, wherein aninner diameter of the flexural deformation portion is set smaller thanan outer diameter of the drainage port so the flexural deformationportion of the connector makes surface-to-surface contact with the outercircumferential surface of the drainage port in a process of fitting theconnector to the outer circumferential surface of the drainage port.